205645040 has 20 divisors (see below), whose sum is σ = 478124904. Its totient is φ = 82257984.

The previous prime is 205645019. The next prime is 205645087. The reversal of 205645040 is 40546502.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1285202 + ... + 1285361.

Almost surely, 2^205645040 is an apocalyptic number.

205645040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205645040 is an abundant number, since it is smaller than the sum of its proper divisors (272479864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

205645040 is a wasteful number, since it uses less digits than its factorization.

205645040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2570576 (or 2570570 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 205645040 is about 14340.3291454555. The cubic root of 205645040 is about 590.2546444604.

The spelling of 205645040 in words is "two hundred five million, six hundred forty-five thousand, forty".